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Hi Reddit! We discovered “Steve,” a mysterious purple light in the sky related to auroras. We’re space and citizen scientists participating in an initiative called Aurorasaurus and working with NASA. Ask us anything!
  • NASASunEarth ,
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Corresponding Author:nasasunearth@thewinnower.com

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EDIT 4:35 pm ET: Thank you all for your excellent questions. It’s been a lot of fun sharing our science with you. We’re signing off now. We have just published a study detailing “Steve,” an aurora-related dancing purple light first spotted – and named! – by amateur photographers. This new information about Steve comes from analyzing satellite data, all-sky cameras and additional citizen-scientist photographs. Steve’s scientific name is now Strong Thermal Emission Velocity Enhancement (which can still be shortened to STEVE). STEVE appears as a faint purple ribbon of light in the sky and is often accompanied by a short-lived, green, picket fence structure. It looks much like an aurora but occurs at lower latitudes closer to the equator. After analyzing satellite data, we learned that STEVE is the visible side of something we were already familiar with: sub auroral ion drift (SAID), a fast moving stream of extremely hot particles. SAIDs appear in areas closer to the equator (like southern Canada) than where most auroras appear. Until now, we never knew SAIDs had a visual component! Studying STEVE can help us paint a better picture of how Earth’s magnetic fields function and interact with charged particles in space. You can help us learn more about STEVE by submitting your photographs and sightings of the phenomenon to a citizen science project called Aurorasaurus (online at aurorasaurus.org or on your device as iOS and Android apps). Check here for more details about how to spot STEVE. Answering your questions today are: Liz MacDonald, space scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and founder of Aurorasaurus Chris Ratzlaff, citizen scientist who first named Steve; runs the Alberta Aurora Chasers Facebook group Burcu Kosar, space scientist at NASA Goddard Matt Heavner, space scientist at the New Mexico Consortium, Los Alamos, New Mexico Bea Gallardo-Lacourt, space physicist at the University of Calgary, Canada Bill Archer, space scientist at the University of Saskatchewan, Saskatoon, Canada Megan Gillies, space scientist at the University of Calgary, Canada We are now live. @NASASun on Twitter